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saramakos: The game was working perfectly up until the latest GOG update the other day. Now the above error message appears every time I try to launch the game. It is installed outside Program Files (D:\GOG\Gothic 3) and I have ensured I have full control permissions over the folder. Anyone have any other suggestions?

I saw in a very old entry in this forum that installing the CEP has fixed it for some people however i understand the current GOG version already has it installed, so I am unsure if I should try installing it over the top.
do ALT/TAB, tab over to the screen shot that has the dialog box. press OK. wait for at least 5 or 10 min. then the game should start. once the game starts and runs, you won't have this issue again.
Kakarot96: You can just wait (ignore the black screen) outside of the process, while googling a bit for instance. After a few minutes, game will finish compiling and you will hear the sound of cinematic (still black screen). Press Esc to cut that cinematic and you will see G3 logo and, after that screen, the main menu.

The next time you run the game you will normally see the first cinematic, also.

Edit: no special permissions over the folder, but installed outside "Program Files" folder. Windows 7 64 bit.
Johnthreesixteen: Wow (so ture) it took about 20 to 30 mins. in/on the Black screen w/ no sound and when I pressed the Esc button the main screen came on. And that's w/ an "non-gaming Lenovo Laptop. Thanks big-time friend & great day/year to you and yours!
You are very welcome, have a great year also!